What Can Patients Believe About Byetta?

San Diego, CAByetta, the diabetes medication made and marketed by Eli Lilly and Amylin, has reportedly been linked to an increased risk of pancreatitis and pancreatic cancer. Some of these reported Byetta side effects may go under the radar, however, because the makers of the drug—and similar drugs—disputed some of the scientific research that went against their medication. The pharmaceutical companies argued that other studies did not find an increased risk of serious side effects and further did not find an association between Byetta and certain reported risks.

Some studies, including those published in the journal Gastroenterology, based on reports to the Adverse Event Reporting System, suggest that use of Byetta is associated with an increased risk of pancreatitis and other serious side effects. In 2008, the US Food and Drug Administration (FDA) issued a warning that it had received reports of six cases of hemorrhagic or necrotizing pancreatitis in patients who used Byetta (known generically as exenatide). Of those six patients, two reportedly died.

Pancreatitis on its own can cause toxins to be released to the patient's bloodstream, but it is rarely fatal. Hemorrhagic or necrotizing pancreatitis, in which the pancreas bleeds and part of it is destroyed, can be much more serious.

At the time, the FDA announced that patients should be taken off Byetta if they show signs of pancreatitis and those who have a history of pancreatitis should be given alternative treatments for their diabetes.

In 2009, the FDA issued a warning letter to Amylin Pharmaceuticals, warning the company that representatives for it and Eli Lilly had made oral misrepresentations about Byetta. Among those, the letter warned, were statements to "promote an unapproved use, broaden the drug's indication, and overstate the efficacy of Byetta." Statements involving unapproved use of Byetta include that it can be used on its own, even though Byetta at the time was only approved as an "adjunctive therapy to improve glycemic control," (in 2009, five months after the statements were made, Byetta was approved to be used on its own.)

Although doctors are free to prescribe medications for unapproved uses, it is illegal for drug companies to market drugs for such use.

Furthermore, representatives of Eli Lilly reportedly claimed that 94 percent of patients in a study lost seven to eight pounds in one month without diet or exercise, while an Amylin representative claimed that 80 percent of patients in a study lost the same weight in a similar time frame. The FDA called this representation of the drug an exaggeration. The FDA's letter requests that representatives of both drug companies immediately stop any promotional activities that violate pharmaceutical regulations.